1. Field of the Invention
Embodiments disclosed herein generally relate to a method and apparatus in which RF voltage is applied at multiple points and at different frequencies.
2. Description of the Related Art
As the demand for larger flat panel displays (FPDs) continues to grow, so does the size of the chambers used to fabricate the FPDs. Additionally, with increasing environmental consciousness, people have been looking to renewable resources such as solar. Solar farms have been proposed which will utilize large area solar panels. Substrates used for fabricating solar panels and FPDs may have an area of about 1 square meter or larger.
There are numerous types of chambers that are used in the process of fabricating FPDs and solar panels including deposition chambers such as plasma enhanced chemical vapor deposition (PECVD) chambers and physical vapor deposition (PVD) chambers, as well as etching chambers.
PECVD, PVD, and etching chambers have been used for semiconductor processing for many years. In recent years, the industry standard for semiconductor wafers is 300 mm in diameter. Thus, the substrates used for fabricating FPDs and solar panels are significantly larger than semiconductor wafers.
Scaling up from a 300 mm wafer chamber to a chamber used to process substrates having an area of 1 square meter or larger is not a simple process. The increase in chamber volume can lead to difficulties such as substrate throughput issues and deposition uniformity issues.
Therefore, there is a need for an apparatus that can process large area substrates.